#!/usr/bin/env python2
# rePython - Python RPC server/client library
#
# Copyright (C) 2013 Andrew Dunai, andunai@gmail.com
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

import os
import sys
import re

INT = ('integer', re.compile('^[-]?[1-9][0-9]*$'), int)
UNSIGNED = ('unsigned integer', re.compile('^[0-9][0-9]*$'), int)
STRING = ('string', re.compile('.*'), str)

def loadEnv(target, *pairs):
	try:
		for item in pairs:
			if type(item) is not tuple:
				continue
			name = item[0]
			reqType = item[1]
			hasDefault = False
			if len(item) == 3:	  # Item has default value
				hasDefault = True
			if name not in os.environ:
				if not hasDefault:
					raise Exception('Environment variable %s not set' % name)
				else:
					target[name] = reqType[2](item[2])
			else:
				value = os.environ[name]
				if not reqType[1].match(value):
					raise Exception('Environment variable %s is not of reqType `%s`' % (name, reqType[0]))
				else:
					target[name] = reqType[2](value)
	except Exception, e:
		print e
		sys.exit(1)
